The most conspicuous visible change that occurs in boys during puberty is:

Options

A. development in voice box.
B. increase in height.
C. production of sperms.
D. increased sweating.

Explanation

**Step-by-Step Solution:**

1. **Understanding Puberty**: Puberty is a developmental stage where boys undergo various physical changes as they transition from childhood to adulthood.

2. **Identifying Visible Changes**: The question asks for the most conspicuous (noticeable) visible change in boys during puberty.

3. **Evaluating Options**: We need to analyze each option provided:
- **Option 1: Development in the voice**: While boys do experience a change in their voice during puberty, this change is not visible; it is audible. Therefore, this option is incorrect.
- **Option 2: Increase in height**: This is a significant and visible change. Boys often experience a growth spurt during puberty, leading to an increase in height due to the elongation of bones. This is primarily influenced by the hormone testosterone. Thus, this option is likely the correct answer.
- **Option 3: Production of sperms**: Although sperm production begins during puberty, it is an internal process and not a visible change. Hence, this option is incorrect.
- **Option 4: Increasing Sweating**: Sweating occurs due to various reasons, including temperature regulation, and is not a specific change associated with puberty. Thus, this option is also incorrect.

4. **Conclusion**: After evaluating all options, the most conspicuous visible change that occurs in boys during puberty is an increase in height.

**Final Answer**: The most conspicuous visible change that occurs in boys during puberty is an increase in height.

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